Ex vivo activation and expansion of γδ T cells for immunotherapy of glioblastoma

2553 Background: Activated γδ T cells will efficiently kill established glioblastoma (GBM) cell lines in vitro. However, their potential for cell therapy has been limited by their relatively small numbers in the peripheral blood and their sensitivity to activation induced cell death (AICD) during ex vivo expansion. Our laboratory developed a method whereby γδ T cells, when stimulated by IFN-γ, IL- 12, and anti-CD2, acquire resistance to AICD and can be expanded in culture with anti-CD3 and IL-2. The γδ T cells expanded by this method are highly cytotoxic to GBM. We have now sought to adapt the laboratory method for human use. Methods: The laboratory method and selection procedure were modified to employ pharmaceutical-grade reagents. Peripheral blood mononuclear cells (1.0 × 106/ml) were stimulated overnight with media containing cGMP grade human serum, IFN-γ, IL-12, and anti-CD2. Media containing human serum, IL-2 and anti-CD3 was then added (1 v/v) and refreshed 1 v/v 3× weekly. The cultures were harves...